Draw-texturing apparatus

ABSTRACT

Undrawn filamentary yarns of thermoplastic synthetic fibers are drawn and false twisted, eliminating undesirable features such as short term flashes and non-uniformity of dyeability on the resulting yarns, by means of a draw-texturing apparatus wherein a pin is disposed at a position in the proximity of a yarn passage between a feed roller and a first delivery roller paired with a separate roller, so that the pin crosses the yarn passage and the axis of the delivery roller transversely and the pin is reciprocated in the direction of said axis and wherein means for positively preventing twist run-back into the upstream yarn passage beyond said first delivery roller is mounted.

United States Patent [1 1 Kishida et al.

[ Sept. 17, 1974 Primary Examiner-John Petrakes [5 7 ABSTRACT Undrawn filamentary yarns of thermoplastic synthetic fibers are drawn and false twisted, eliminating undesirable features such as short term flashes and nonuniformity of dyeability on the resulting yarns, by means of a draw-texturing apparatus wherein a pin is disposed at a position in the proximity of a yarn passage between a feed roller and a first delivery roller paired with a separate roller, so that the pin crosses the yarn passage and the axis of the delivery roller transversely and the pin is reciprocated in the direction of said axis and wherein means for positively preventing twist run-back into the upstream yarn passage beyond said first delivery roller is mounted.

7 Claims, 3 Drawing Figures PAIENIEB H 3.835.632

' sum; nr .2 I

PAIENTEUSEPITIWI 3,835,632

SHEET 2 OF 2 1 DRAW-TEXTURING APPARATUS The present invention relates to a draw-texturing apparatus. More particularly, the invention relates to an improved apparatus for manufacturing false twisted and crimped yarns at high efficiency by drawing and false twisting multifilamentary yarns of thermoplastic synthetic fibers such as polyester and polyamide fibers.

It has been a practice that crimped yarns of thermoplastic synthetic fibers such as polyester and polyamide fibers are prepared by drawing spun filamentary yarns at a prescribed draw ratio to orient fiber-constituting molecules and attaining desired strength and elongation, and thereafter, false twisting the so drawn yarns.

Savings in labor and reduction of the manufacturing cost by improving of the manufacturing steps have recently been demanded in the art, and hence, there have been adopted methods in which the above two steps, namely the drawing step and the false twisting step, are combined in one step. More specifically, the false-twist processing is conducted subsequently to, or simultaneously with, the drawing treatment. When the drawing treatment and false-twist processing are carried out at one step, however, the resulting crimped yarns result in a problem so that when they are formed into knitted articles or woven fabrics, such objectionable features as short term flashes and non-uniformity of dyeability are readily brought about. Accordingly, development of an improved draw-texturing apparatus according to which crimped yarns being free of such defects can be manufactured at high efficiency has been greatly demanded in the art.

It is therefore a primary object of this invention to provide an improved draw-texturing apparatus in which crimped yarns causing none of such objectionable features as short term flashes and non-uniformity of dyeability can be easily manufactured at a high efficiency. Other objects and features of this invention will be apparent from the description and claims given hereinafter by reference to the accompanying drawings.

In accordance with this invention, there is provided a draw-texturing apparatus wherein a pin is disposed at a position in the proximity of a yarn passage between a feed roller for taking a yarn from an undrawn yarn supply source and feeding the yarn into the apparatus and a first delivery roller paired with a separate roller, so that the pin crosses the yarn passage and the axis of the delivery roller transversely and the pin is reciprocated in the direction of said axis, and wherein means for positively preventing twist run-back into the upstream yarn passage beyond said first delivery roller is mounted.

An apparatus of this invention in which the falsetwist processing is conducted subsequently to the drawing treatment will now be illustrated by reference to the accompanying drawings, in which:

FIG. 1 is a perspective view illustrating the drawtexturing apparatus of this invention; v

FIG. 2 is a sectional side view illustrating an embodiment of the pin-reciprocating mechanism in the apparatus shown in FIG. I, and;

FIG. 3 is a perspective view illustrating an embodiment of the yarn-nipping mechanism in the apparatus shown in FIG. 1.

Referring to FIG. 1, undrawn yarn Y, is taken out of a package 1 of undrawn yarn and fed to a drawing zone by means of a feed roller 3 pressed by a cot roller 2 where the yarn is turned between a multi-grooved guide 2 and the cot roller 2. Then, the yarn contacts a draw pin 4 (there may be a plurality of pins) and then is wound by a draw roller 5 (first delivery roller) and a separate roller 5 paired therewith. Between the feed roller 3 and draw roller 5 the yarn is drawn at a prescribed draw ratio (usually at a draw ratio of 1.3 to 4.0). The so drawn yarn Y is contacted with a grooved heater 6 and heated by said heater, and thus, twists given to the yarn by false-twisting means 7 are thermally set and fixed. Then, the yarn arrives, while being untwisted, at a stretch roller 8 (second delivery roller). In addition, there are provided a yarn-breakage detecting means 31 at a portion of the take-up means 9 and a yarn cutter 32 at a position upstream of the feed roller 3 whereby the supply of the undrawn yarn is stopped at the time of yarn-breakage. As the falsetwisting means, there may be employed false-twisting spindles, false twisters of the frictional system using twist bushes, discs, friction ropes, etc. and other means. The so drawn and false twisted yarn is formed in a package by take-up means 9 such as a ring twister, a friction roller type winder and a spindle type winder.

In this embodiment, the undrawn yarn may be introduced into the apparatus from a creel truck, on which undrawn yarn packages are mounted, conveyed on the upper portion of the apparatus.

The foregoing structure is not substantially different from the structure adopted in the conventional drawtexturing apparatus. The characteristic features of the apparatus of this invention will now be described.

In the apparatus of this invention, the draw pin 4 is reciprocated in the direction of the axis of the draw roller 5 as indicated by an arrow A in the drawings and simultaneously, a nip roller 11 coated with an elastic member such as rubber is pressed against the draw roller 5 to nip the yarn wound on said roller 5. In the embodiment shown in the drawings, the nip roller 11 is so arranged that at least one turn of the yarn about the draw roller 5 at the feeding-in side thereof is not nipped.

The mechanism for reciprocating the draw pin will now be described with reference to FIG. 2. The draw pin 4 is fixed via an arm on a slide bar 13 extending in the longitudinal direction of the machine, and this slide bar 13 is slidably supported on a guide bracket 14 and always pressed against a rotated and driven eccentric cam 16 by a repulsive force of a spring 18. This eccentric cam 16 is held on a bracket 19 by means of a bearing 17 and is attached eccentrically to a shaft 15 rotated by a suitable rotating and driving device (not shown), in such a manner that the cam is swung and rolled in correspondence to the rotation of the shaft 15. The draw pin 4 is pressed against this eccentric cam 16 via the slide bar 13 and it is reciprocated in the direction indicated by the arrow A by an eccentric amount of twice the eccentric amount ofe of the eccentric cam during one rotation of said cam l6, or 2e.

Similar effects can be obtained by rotatably supporting the slide bar, mounting an oscillating arm on the end thereof and pressing said arm against a cam of triangular form, though this embodiment is not shown in the drawings. The slide bar may be rotated by an air cylinder.

The mechanism for nipping the discharge side of the yarn will now be described with reference to FIG. 3. The nip roller 11 is fixedly mounted on an arm 21 pivoted at an end thereof and the other end of this arm 21 is connected to a spring 22, so that the nip roller 11 is pressed against the draw roller by an attractive force of the spring 22. Thus, the yarn is nipped between the draw roller 5 and the nip roller 11.

In the apparatus of this invention having the abovementioned structure, when the draw pin 4 is reciprocated in the foregoing manner, the yarn is rolled and moved on the draw roller 5 in the direction of the reciprocating movement of the draw pin and individual filaments constituting the yarn are entangled with one another with rolling movement and then false twisted. Accordingly, although in the conventional apparatus there is brought about such an undesired phenomenon that specific filaments positioned in the central portion of the yarn are allowed to keep the same position for a long time and therefore are not twisted for a long time, occurrence of such an undesirable result is substantially prevented in the apparatus of this invention. Because the filaments are entangled with one another, prolongation of non-crimped portions in specific filaments can be prevented and all the filaments are well dispersed. It is especially desired that at least one turn on the feeding-in side of the yarn wound on the draw roller is not nipped by a nip roller, because in such case the above undesirable effect is further enhanced.

Further, in the apparatus of this invention, since the yarn on the draw roller 5 is nipped by the nip roller 11, the run-back of twists from the false-twisting means 7 is positively and uniformly stopped at the nip point and hence, such an undesirable result wherein the twist runback length is changed with the lapse of time can be completely prevented from occurring. For the twist run-back preventing means, for example, a tensor, disposed between the first delivery roller and the heater, cooperating with the pin may be utilized instead of the above-mentioned nip roller.

Therefore, in the apparatus of this invention, the uneven twisting among fiiaments and in the yarn portions caused by the foregoing undesirable phenomena can be completely prevented, with the result that when crimped yarns manufactured by the apparatus of this invention are formed into knitted articles or woven fabrics, the occurrence of such objectionable features as short term flashes and non-uniformity of dyeability can be greatly reduced and the quality of the products can be greatly improved.

Still further, in the apparatus of this invention, since the draw pin is reciprocated, the yarn disposed under high tension between the feed roller and draw roller can be moved easily and assuredly. Moreover, since the yarn-pressing point of the nip roller is displaced in the axial direction with the lapse of time, abrasion of specific points of the nip roller by a drilling action of twisted yarns can be prevented. and there is attained such a secondary effect that the life ofthe nip roller can be prolonged several times as compared with the case where the draw pin is not reciprocated.

In the apparatus of this invention, the nip roller 11 is coated with a urethane rubber having a Shore hardness A of 55 to 85. When a urethane rubber having a hardness within the above range is used as a coating of the nip roller, twist run-back of the yarn can be definitely stopped at the nip point, and even when the yarn is broken at a point after the draw roller, it is not wound on such a urethane rubber-coated nip roller but is wound on the draw roller composed of a mirrorpolished metal, and the nip roller is not damaged at all. in contrast, when the nip roller is coated with an NBR (nitrilbutadiene rubber), SBR (butadiene-styrene rubber) or the like, the broken yarn is wound on the soft nip roller, though the reason has not been elucidated, and the roller is so damaged that it cannot be used any longer and it should be exchanged for a new one, which results in troubles and difficulties in the apparatus maintenance.

When the apparatus of this invention is used for drawing and false twisting of polyester yarns, it is preferred that the draw pin is heated. Further, the feed roller may also be heated.

In the apparatus of this invention, a second heater is optionally disposed between the stretch roller and takeup means, so that the elasticity and elongation of the resulting crimped yarn are maintained at desired levels.

Furthermore, in the apparatus of this invention, the false-twist processing can be accomplished simultaneously with the drawing operation, by appropriately changing the peripheral speed of the draw roller.

This invention will now be illustrated by reference to Examples.

EXAMPLE 1 With use of the apparatus of this invention such as illustrated in H65. 1, 2 and 3, a nylon yarn of 20 deffi fil was drawn at a draw ratio of 3.30 and falsely twisted by employing a twist bush as false-twisting means 7. During this operation, the reciprocating displacement of the draw pin was adjusted to 2 mm, and the reciprocating movement was conducted continuously at a frequency of one cycle per hour. Yarn take up speed was 500 m/min.

The resulting crimped yarn was knitted into panty hose and the non-uniform knitting preventive effect was evaluated by naked eye observation by experts according to the following scale:

Grade Naked Eye Observation 5 no defects 4 some defects are observed but they have no significant influences on the quaiity of the product (product of special grade) 3 relatively many defects but they hardly have parcicularly bad influences on the quaiity of the product [product of common grade) considerable defects (product of low grade) 1 highly excessive defects (product cannot be used) 5. vided, had a non-uniformity preventive effect of a grade of 3.0.

EXAMPLE 2 A nylon yarn of 18 de/6 fil was drawn and falsely twisted under the same conditions as in Example 1 except that the frequency of the reciprocating movement of the draw pin was changed to 6 cycles per hour and the yarn take up speed was 800 the resulting crimped yarn, m/min. In the non-uniform knitting preventive effect was ofa grade of4 to 5. When the draw-false twisting was conducted with use of conventional apparatus of the draw pin-fixed type, the grade of the nonuniformity knitting preventive effect was 3.0. From these results, it will readily be understood that the quality of the resulting crimped yarn is highly improved when the apparatus of this invention is employed.

EXAMPLE 3 A polyester yarn of 150 de/36 fil was drawn at a draw ratio of 2.80 and falsely twisted by means of the apparatus of this invention such as illustrated in the drawings. In this operation, the draw pin was heated and a false-twist spindle was employed as the false-twisting means 7. The displacement distance of the reciprocating movement of the draw pin was adjusted to 3 mm, the frequency of the reciprocating movement was 10 cycles per hour and the yarn take up speed was set at 200 m/min. The resulting crimped yarn was knitted into a hosiery article and it was subjected to the dyeing test to evaluate dyeability. For comparison, the same starting filamentary yarn was treated by means of conventional apparatus in which the draw pin was not reciprocated and no nip roller was provided, and the resulting crimped yarn was knitted into a hosiery article. Then, the comparative sample was similarly subjected to the dyeing test. As a result of naked eye observation, it was found that occurrence of non-uniform dyeability was much more reduced in the sample according to this invention than in the comparative sample and the quality of the resulting crimped yarn can be greatly improved by use of the apparatus of this invention.

What we claim is:

1. In a draw-texturing apparatus for draw-falsetwisting filamentary yarns of thermoplastic synthetic fibers which comprises a source of undrawn yarn, a

feed roller for feeding a yarn taken out of said yarn source, a first delivery roller paired with a separate roller disposed at a position downstream of said feed roller, a pin disposed at a position in the proximity of a yarn passage between said feed roller and said first delivery roller in transversal condition to said yarn passage, a heater mounted at a position downstream of said first delivery roller for thermally setting and fixing a yarn delivered from said first delivery roller in the twisted state, means for imparting false twists to said yarn delivered from said first delivery roller while passing through said heater, take-up means for winding the false twisted yarn on a bobbin, a second delivery roller disposed between said false-twisting means and said take-up means, said first delivery roller having an axis disposed transversely to an axis of said pin, the improvement comprising in combination, means for reciprocating said pin substantially in the direction of the axis of said first delivery roller and means for positively preventing twist run-back into the upstream yarn passage beyond said first delivery roller.

2. A draw-texturing apparatus according to claim 1 wherein said twist running back preventing means is a nip roller for nipping the yarn wound on said first delivery roller.

3. A draw-texturing apparatus according to claim 2 wherein said nip roller is urged to said first delivery roller so that it does not nip at least one turn of said yarn about said first delivery roller at the feeding-in side thereof.

4. A draw-texturing apparatus according to claim 2 wherein said nip roller is coated with a urethane rubber having a Shore hardness A of 55 to 85.

5. A draw-texturing apparatus according to claim 1 wherein said pin-reciprocating means comprises a bar rigidly supporting said pin and a cam means for reciprocately displacing said bar, a driving means for periodically driving said cam means with a predetermined frequency.

6. A draw texturing apparatus according to claim 1 wherein said pin is heated.

7. A draw texturing apparatus according to claim 1 wherein a second heater is disposed between said stretch roller and said take up means.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N Dated 17 Inventor(s) TAKASHI HIDA and It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 9, after "800" insert m/min. In

line 10, cancel "m/min. In".

Signed and sealed this 4th day of March 1975. I

(SEAL) Attest:

C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officer and Trademarks V 4 P0405) USCOMM-DC 60376-F'69 ".5. GOVEINMENY PRINTING OFF'CEI 9.9 J$6-334 

1. In a draw-texturing apparatus for draw-false-twisting filamentary yarns of thermoplastic synthetic fibers which comprises a source of undrawn yarn, a feed roller for feeding a yarn taken out of said yarn source, a first delivery roller paired with a separate roller disposed at a position downstream of said feed roller, a pin disposed at a position in the proximity of a yarn passage between said feed roller and said first delivery roller in transversal condition to said yarn passage, a heater mounted at a position downstream of said first delivery roller for thermally setting and fixing a yarn delivered from said first delivery roller in the twisted state, means for imparting false twists to said yarn delivered from said first delivery roller while passing through said heater, take-up means for winding the false twisted yarn on a bobbin, a second delivery roller disposed between said false-twisting means and said takeup means, said first delivery roller having an axis disposed transversely to an axis of said pin, the improvement comprising in combination, means for reciprocating said pin substantially in the direction of the axis of said first delivery roller and means for positively preventing twist run-back into the upstream yarn passage beyond said first delivery roller.
 2. A draw-texturing apparatus according to claim 1 wherein said twist running back preventing means is a nip roller for nipping the yarn wound on said first delivery roller.
 3. A draw-texturing apparatus according to claim 2 wherein said nip roller is urged to said first delivery roller so that it does not nip at least one turn of said yarn about said first delivery roller at the feeding-in side thereof.
 4. A draw-texturing apparatus according to claim 2 wherein said nip roller is coated with a urethane rubber having a Shore hardness A of 55 to
 85. 5. A draw-texturing apparatus according to claim 1 wherein said pin-reciprocating means comprises a bar rigidly supporting said pin and a cam means for reciprocately displacing said bar, a driving means for periodically driving said cam means with a predetermined frequency.
 6. A draw texturing apparatus according to claim 1 wherein said pin is heated.
 7. A draw texturing apparatus according to claim 1 wherein a second heater is disposed between said stretch roller and said take up means. 